Drying device



ranma nu. iv, 192s.

ED stares4 CHARLES E. GUBBIEB, 0F CHICAGO, ILLNOIS.

DRYING DEVICE.

Applicatie!! lied June 23, 1924. Burial No.. WZL'SS.

This invention relates to the art of drying and is particularly applicable for use in connection with open ended drying rooms or tunnels, through which the ,material treated y t is caused to travel during the drying operation.. 'lhe object of the invention is principally to increase the efficiency of drying methods and apparatus, and also to overcome la serious tendency to uneven drying, due to ld the stratification of the air in existing apparatus of the saine general type.

lhe open ended dr ing room now4 com inonly in use has delivered thereto heated and otherwise properly conditioned air,

it either at one or several points in the room, the air heing caused to travel along the room and is usually exhausted at the open ends. Due to the fact that the ends of the roomi are open and because heated air used in the dry ing process is of considerably higher temperature, and therefore much lighter than the air outside the room, the cool outer air is free to enter the drying room at the` lower parts of its open ends and travel inwardly possibly W8 to M of the length or so, before meeting the currents of heated air, land rising and being turned backwardly and carried out ofthe room with the heated air.

"fo overcoine this difficulty and needless loss of heat and slow and uneven drying, it is pro osed by the present invention to :forcibly eftect proper circulation and prevent the entrance of unconditioned cool air by successively blowing into the apparatus and withdrawingF therefrom, at suitable locations a continuous stream of properly conditioned air which may in some cases be re heated and rewashed or humidied at the successive stages. The result is that only such air as is actually desired for the dryin operation passes into the drying room, an the heat and rnoisture of this air is expended in useful worhz, except for radiation losses which are inherent in any such apparatus.

ln the drawings lill til

hig., l is a plan of an oven, wide enough` for a plurality of conveyor systems or pasw sageways disposed side by side.

llig. 2 is a vertical section on the line der rip. i.

lhis invention nia be carried intoeh'ect by the use of any o, the connnon forms of open ended drying rooms or tunnels, either singly or in series9 or arranged side hy side as is cornrnon in the art to suit the retpiireinanteeD sonne articles or materials being 1re-coated or treated between successive drying operations taking' placethrough a series of drying rooms.. y

rihe construction shown in the drawings `is a rectangular room or tunnel having located along its length a series of air deliverlng conduits for uniformly distributing properlyconditioned air to the drying room 1n a downward direction. 'lhe general path of travel of the air in the room is opposite' to the direction of travel of the rnaterial operated upon. 'lhe drst system of air deliveru ing conduits receives fresh air from the ex terior ofthe drying room, which air is Hirst washedy humidil'ied and heated. The re niainingA air delivering conduits also .cornrl municate with air conditioning ap aratus, but the air for these conduits is wit drawn from the 'drying roona at suitalole intervals. The' used air is finally pumped out of the drying room at the entering end for the mav terial operated upon. Byv this arran ement the drying may be edected by air w ich is reconditioned or has its temperature changed and its moisture content varied at diderent stages in the process of drying and without needless loss of heat.,

Referring to the drawing, a suitable floor space is shown for receiving the drying room9 consisting of side walls l and 2 and its own ceiling 3, spaced below 'the ceiling d of the door within which the drying room is located. lhe air conditioning apparatus may be located out of the way above the plane of the ceiling 3. 'llhe articles' or inaterial treated during the drying process travel from left to right as indicated by the arrows 5, which are also in the center line of a plurality of continuous conveyors for carrying materials to be dried, hut which conveyors are not shown in the drawingo lhe general direction ofthe air through the drying roorn is frena right to left, oppositely to the direteIl tion of the material treated. Ilhe fresh air intahe is indicated by the nuineral d and sup-- plies air to the first set of air delivering con duits l. Before entering the distrihuting conduit it the air passes lthrough a pre-heater 8, washer and hunuiditder d, a rnain heater ld and fan ll. @eine of' the air passing through the heater lil and fan lll. to the distributor 'l' is preferably talren frein the die charge end l2 of the drying' roorn by means of intalre nozzles ld, connected with the air heater l0 by the conduits ld..

ha indicated hy the arrowa lll in liig., il

liltl lltl articles or material on'the conveyors and then to the left toward an intake nozzle 16.l

.This intake nozzle has the air drawn through it by afan ,17 which then causes the same air to be discharged through an air distributing system 7 The nozzles indicated in the in which the pressure is evenly distributed drawings are of the constructionfully illustrated in the patent to Burt S. Harrison, No. 1,506,904, vin which a tapering conical tube is provided with a slit or openlng along one side to furnish a long narrow opening throughout the length. The nozzles of all the air intake and distributing devices are designed to effect an` even or uniform flow of the air in the drying room. The' used air entering one of the intakes 16 or 16 may have its temperature or moisture content varied by traveling .throughthe heater 18 or through a heater 19 and humidifier 20,

and thus be suitably reconditioned to vary ,the nature or rate of its work upon the material passing throu h the drying room. Thus, in some cases, t e air may haveits maximum humidity at the entering end and its maximum temperature at the work discharge endof the drying room as required for best results, depending upon what work is to be erformed The used air is finally exhausted from the work entering end of the d ing room by the exhaust nozzles 21, throng which the air is drawn by a ventilating fan 22.

, 'In the operation of the device, the articles treated are caused to travel from left to right as indicated by arrows 5, whereas the eneral direction of the air qumped throu h t e 'ng room is from vrig t to left. T e conditlon of this air is chan ed to suit the operation by successively wit drawing it at intervals in the dr ing room and reconditioning the air an aga-in forcibly delivering such air to the drying room with the air uniforml distributed and havin rection whic will insure substantia y uni, form contact of the air all over the surfaces of the articles treated. In some cases the distributing conduits o r nozzles are prefer- A navarra ence in the weight between the warm air inside the oven and the cooler air outside the voven,the cooler air will rush in alon lthe floor of the ovens, dilute and mix wit the warm air, so that the ends, for a considerable distance such asl from 1,/8 to 1/1 the length of the ovens, will be coldest at the bottom, cool in the middle and only fairly Warm at the top.

This fault isordinarily overcome by the use of a much' greater volume of air than is needed to accomplish the drying work, with a. result thatA there is vented at the ends of the' ovens a considerable quantity of air which has not performed useful wor and the eieiency of the oven becomes very low when compared with a completely locked oven,`in which the heat is .entirely trapped.

,To overcome this disadvantage of the open ended or unlocked ovens, the idea is to use the same quantity of air over and over again by icklng it up at the roof of the dry room an recirculating it over the work so that the heat in saine is absorbed in useful drying and not wasted at the ends of the ovens.

Although but one specific embodiment of this invention has been herein shown and described, it willbe understood that numerous details of the construction shown may be altered or omitted without departin from the spirit of this invention as define by the following claims.

I claim: p

1. In an ogen ended drying room havin work to be ried entering at one end an leavin at the opposite end, suction nozzles "locate above the entrance and exit of the room,- a series of air distributor nozzles located acro the upper part'along the len h of the room for dlrectmg air downwar ly, suction nozzles located between said air distributors, means for drawing air out through the suction nozzle at the entrance, and means for drawing air out through each succeeding nozzle and discharging the same .into the next preceding distributor.

2. 'In a drying room a series of spaced distributor ducts extending across the up er portion of the room, a plurality of istributor nozzles extending from both sides of the ducts and paralle to the length of the room, suction nozzles extending acro the room at the ends ot the distributor nozzles, means for drawing air out through each of the suction nozzles and dischargin the same into the next preceding distri utor duct, and means for conditioning the air Adrawn out through the'l suction nozzles.

Signed atGhicago this 10th day of June, 1924.

CHARLES H. CURRIER. 

